basis-map coefficients of A371080, shifted → basis A013610

nonnegative coefficients only rational roots

Proved for all n: all roots real, in (−∞, 0] · coefficients of one sign · Hadamard kernel what this means

Recurrence
\(P_{n}(x) = \left(-2 + 3\,x + 3\,n\right)\,P_{n-1}(x)\)
\(P_{0}(x) = 1\)

Rows ?

nx0x1x2x3x4x5x6x7x8x9x10x11x12x13x14Pn(1)
011
1134
2415928
32811710827280
428012541431594813640
53640171422236512015283524358240
65824028519240926625933581405123937291106560
71106560559336886316306155163232470047968251030218724344320
824344320126373776206675964161308476696088891752710425617062012046561608608000
96086080003232377360554602042846527397922224147653647004267116623962127152187676371968317041024000
1017041024000923323900801649857040641469147754607623435366024788562435520648373770589799059639490285403559049528271744000
1152827174400029134271644805391553996224504931515145228040092898409971484964652357666831523750228890139665181602673935551039262417714717961239296000
12179612392960001006413388243201920531173650561878513771380401104842613089164231507674933011007512716563198237787209024736848414320990935350115552988137200870531441664565853952000
13664565853952000377761325438784074078893589800327526660306202648465147179984401218971106236519585342232007608211063705194170191509976752956115187700603791057274116474843021833131265927159432326582634158080000
14265826341580800001530982277373696003076484141223648003232900803250460162086388529123684248983884034561035627060259901388714585749037896322392310225943349710605010500384387854066470175109031082611977970257945757070147829691143053268797440000

Computed in your browser ?

Technical details
Node id
n-b0592fccca597966 · revision 1 · JSON
Definition source
derived:basis_map_A013610
Fingerprint
f6-f061f7c708547767

Observed on the stored rows ?

  • Degrees: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14 (affine: slope 1, intercept 0)
  • Palindromic rows: no
  • γ-positive (gamma_positive): no
  • Nonnegative coefficients (nonn): yes
  • Only rational roots (rr_by_factors: every nonzero row is a product of linear factors over ℚ): yes

OEIS matches ?

OEIS submission text ?

Fields to paste into an OEIS submission: the example %e, the formula %F and programs %t (Mathematica) and %o (PARI/GP) that list the same rows. For an OEIS link the row numbers, the offset and the orientation are those of the entry, as matched; the matched terms were compared with the published ones, which identifies the node with the entry on a finite prefix, not for every n. The PARI/GP program is not machine-checked here.

The atlas's own rows: n = 0, …, ascending powers of x
%e Example
Triangle begins:
  0:         1;
  1:         1,          3;
  2:         4,         15,          9;
  3:        28,        117,        108,         27;
  4:       280,       1254,       1431,        594,         81;
  5:      3640,      17142,      22365,      12015,       2835,       243;
  6:     58240,     285192,     409266,     259335,      81405,     12393,       729;
  7:   1106560,    5593368,    8631630,    6155163,    2324700,    479682,     51030,     2187;
  8:  24344320,  126373776,  206675964,  161308476,   69608889,  17527104,   2561706,   201204,   6561;
  9: 608608000, 3232377360, 5546020428, 4652739792, 2224147653, 647004267, 116623962, 12715218, 767637, 19683;
%F Formula
The row polynomials satisfy P(n,x) = (3*n-2+3*x)*P(n-1,x) for n >= 1, with P(0,x) = 1.
%t Mathematica
P[0, x_] := 1;
P[n_, x_] := P[n, x] = Expand[(3*n - 2 + 3*x)*P[n - 1, x]];
Table[CoefficientList[P[n, x], x], {n, 0, 9}] // Flatten
%o PARI/GP
P(N) = {my(v = vector(N + 1)); v[1] = 1; for(n = 1, N, my(i = n + 1); v[i] = (3*n - 2 + 3*x)*v[i - 1]); v};
row(n, p) = {my(c = Vecrev(p)); c};
T(N) = {my(v = P(N)); concat(vector(#v, i, row(i - 1, v[i])))};
T(9)

Generated with polytool c48629374597.

Proved properties

  • Real-rooted. Every row P_n, n >= 0, is zero or real-rooted with all roots in (-inf, 0]
    Every polynomial of the sequence has only real roots, inside the stated interval.
    by the cited steps: e-8877bf17db51e7c6
  • Coefficients of one sign. Every nonzero row, n >= 0: the coefficients of P_n have one sign
    All coefficients of each polynomial have the same sign (after x -> -x when alternating).
    derived from the cited steps by a stated theorem: e-8877bf17db51e7c6
  • Hadamard kernel (Malo). Rows P_n, n >= 0, are Hadamard kernels (preserve real-rootedness)
    Multiplying the coefficients of any real-rooted polynomial termwise by those of a row (Hadamard product) gives a real-rooted polynomial again.
    derived from the cited steps by a stated theorem: e-8877bf17db51e7c6

Proof chains

1 incoming proof step. Each step is expanded back to the roots of the proof DAG, the theorem checks of a node's own rule. JSON

No candidate equalities or related sequences.